Question: Which isotope of antihydrogen with a gravitational interaction has the smallest electric charge ?
Paraphrase: The isotope of antihydrogen with gravitational interaction possessing the smallest electric charge is?
SPARQL (Wikidata): select ?ent where { ?ent wdt:P31 wd:Q31804375 . ?ent wdt:P2200 ?obj . ?ent wdt:P517 wd:Q11412} ORDER BY ASC(?obj)LIMIT 5 
Answer: antideuterium